1. Field of the Invention
This invention relates to an arrangement for mounting a window unit to a building frame, and more particularly to an arrangement for mounting a window unit in an opening of a building frame through upper and lower connecting metal fixtures fixedly secured to the upper and lower parts of the opening of the building frame, and/or a reinforcing transverse frame secured at an intermediate position between the upper and lower connecting metal fixtures.
2. Description of the Prior Art
In a window unit which is generally used, an upper framework and a lower framework are formed by assembling an upper frame, a lower frame and left and right longitudinal frames and disposing a transom transversely between the longitudinal frames, and then a panel member is mounted on each of the upper and lower frameworks thereby forming an upper window unit and a lower window unit.
To mount the above-mentioned window units on a building frame to construct an external wall; in other words, to construct a curtain wall with window units, mullions are connected to the building frame, window units are mounted between the mullions, and window units are mounted through fasteners onto the building frame.
Since such a window unit is formed by transversely connecting an upper frame, a transom and a lower frame between left and right longitudinal frames, it can be mounted on a building frame by connecting the left and right longitudinal frames to the mullions and the fasteners.
However, in case a pc board is mounted on a building frame, and a window unit, which is comprised of an upper window unit and a lower window unit which have separately been assembled, is mounted in an opening formed in the pc board, it is very troublesome to mount the longitudinal frames in the opening of the building frame using mullions and fasteners according to the conventional practice, because the longtidinal frames need to be mounted in a narrow opening. Further, in case the window unit is a transverse multiple window, a long transom must be used which is liable to be deformed or bent either in the indoor or in the outdoor direction when it is subjected to a strong wind.
Further, as disclosed in Japanese Laid-Open Utility Model Application No. SHO 60-83617, there, is known a window unit wherein a lower transverse frame which is disposed below a lower window frame forming a window unit so as to form a wall-through portion between the lower window frame and the lower transverse frame, the arrangement being made such that the outside air can be introduced through the through-wall portion into the room.
In such a window unit, the lower window frame is integrally formed with suspension plates, the suspension plates are abutted against a lower frame, and the lower window frame is connected to the lower transverse frame, thereby preventing the lower window frame from being deformed or bent by the action of wind pressure either in the indoor or in the outdoor direction. According to this arrangement, however, the outside air inlet holes must be formed in the suspension plates, and not only the fabrication becomes troublesome, but also the area of opening through which the outside air is introduced is reduced with the result that the outside air cannot be supplied fully into the room.
To solve this problem, it is only necessary to dispose the lower window frame apart vertically from the lower transverse frame. However, by so doing, the longitudinal ends of the lower window frame is connected and supported only by the left and right longitudinal frames, and the lower window frame cannot be supported directly by the building frame, thus causing the lower window frame to be deformed or bent by the action of wind pressure etc. either in the indoor or in the outdoor direction.
This tendency becomes conspicuous, particularly in case of a transverse multiple window wherein window units are connected continuously in the transverse direction.